Cancer patients may benefit from sessions with trained music therapists or from listening to music. A new Cochrane systematic review shows using music can reduce anxiety in cancer patients, and may also have positive effects on mood, pain and quality of life. Music and music therapy are used in a wide range of clinical settings. Treatments range from patients listening to pre-recorded music, to music therapists engaging patients in music experiences to improve psychological and physical well-being. In the review, researchers focused on trials with patients with any kind of cancer who were offered music or music therapy sessions.

The researchers analysed evidence from 1,891 patients taking part in 30 trials. 13 trials used trained music therapists, while in the remaining 17 trials, patients listened to pre-recorded music. How long and how often patients participated in music sessions varied greatly among trials. The results show that compared to standard treatments, music reduced anxiety considerably based on clinical anxiety scores. Some trials reported much larger beneficial effects than others. The results also suggest that music therapy may increase patients' quality of life. There was some benefit in music for mood and pain, although not depression. Smaller beneficial effects were seen for heart rate, respiratory（呼吸的） rate and blood pressure.

"The evidence suggests that music interventions may be useful as a complementary treatment to people with cancer," said lead researcher Joke Bradt of the Department of Creative Arts Therapies at Drexel University in Philadelphia, US. "Music interventions provided by trained music therapists as well as listening to pre-recorded music both have shown positive outcomes in this review, but at this time there is not enough evidence to determine if one intervention is more effective than the other."

"It should be noted, however, that when patients can't be blinded to an intervention, there is an opportunity for bias（偏见） when they are asked to report on subjective measures like anxiety, pain mood and quality of life," said Bradt.

The researchers point out that the quality of evidence for some outcomes was low because of the small numbers of trials that have been carried out. Further trials could help increase certainty in the findings and improve understanding of music's impact on distress, body image and other aspects, for which research is currently too scarce to draw any conclusions.